HP D315 USB Programming, USB Configuration, USB Control, USB Interface Configuration Registers

Chapter 5 Input/Output Interfaces

5.7.2 USB PROGRAMMING

Programming the USB interface consists of configuration, which typically occurs during POST, and control, which occurs at runtime.

5.7.2.1 USB Configuration

Each USB controller functions as a PCI device within the MCP component and is configured using PCI Configuration Registers as listed in Table 5-17.

Table 5–17. USB Interface Configuration Registers

Table 5-17.

USB Interface Configuration Registers

PCI			PCI
Config.		Reset	Config.		Reset
Addr.	Register	Value	Addr.	Register	Value
00, 01h	Vender ID	10DEh	0Fh	BIST	00h
02, 03h	Device ID	[1]	10h	OHCI Memory Base Addr.	0s
04, 05h	PCI Command	0200h	3Ch	Interrupt Line	00h
06, 07h	PCI Status	00B0h	3Dh	Interrupt Pin	01h
08h	Revision ID	A1h	3Eh	Minimum Grant	03h
09h	Class Code	0C0310h	3Fh	Maximum Latency	01h
0Ch	Cache Line Size	00h	46h	Power Mgmt. Capabilities	FE02h
0Dh	Latency Timer	00	4Ch	Specific Configuration	[2]
0Eh	Header Type	00h	50h	USB Port Mapping	[3]

NOTE:

[1]For D315 = 01C2h; for D325 = 0067h (Cntlr #1), 0067h (Cntlr #2), or 0068h (Cntlr #3)

[2]USB #1 = 02h USB #2 = 03h

[3]The BIOS will configure this register for 2/4 operation.

5.7.2.2USB Control

The USB is controlled through I/O registers as listed in table 5-18.

Table 5–18. USB Control Registers

Table 5-18.

USB Control Registers

I/O Addr.	Register	Default Value
00, 01h	Command	0000h
02, 03h	Status	0000h
04, 05h	Interrupt Enable	0000h
06, 07	Frame Number	0000h
08, 0B	Frame List Base Address	0000h
0Ch	Start of Frame Modify	40h
10, 11h	Port 1 Status/Control	0080h
12, 13h	Port 2 Status/Control	0080h
18h	Test Data	00h

5-24Compaq D315 and hp d325 Personal Computers Featuring the AMD Athlon XP Processor

Second Edition – April 2003